Caloric engine



2 'Sheets-'Sheet 1 (Model.)

J. JENKINS.

.m P mvo n E G .r O na. C

N. PEVIERS, PHOTQUTMOGRAPHER, WASHINGTON. D C.

(Model.)

2 Sheets-Sheet 2,

J.. JENKINS. Calorie-Engine.

will! Patented .lune 8,1880.

l lllllll N. PETERS. FMGYO-LI'TNOGRAPHER. WASHlNGTON. D C.

ATENT Critica.

JABEZ JENKINS, OF PHILADELPHIA, PENNSYLVANIA.

CALomc ENGINE.

SPECIFICATION forming part of Letters Patent No. 228,643, dated June 8, 1880.

Application filed March 30, '1880.

To all whom t may concern Be it known that I., JABEZ JENKINS, a citizen of the United States, residing at Philadelphia, in the county or" Philadelphia and State of Pennsylvania, have invented new and useful Improvements in Calorie Engines, of which the followingis a specication.

My improved engine` is chiey designed as a motor for sewing-machines and the like, and in which the expansive power of heated air is employed as the motive agent. It embraces a construction and combination of elements, making a new. organized caloric engine, in which a suitable air-heater is combined with a flexible-diaphragm piston-motor having direct connection with the crank power-transmittin g shaft, and a continuous communication with said heater; and a flexible-diaphragm air-pump having direct connection with the flexible-diaphragm piston-motor, and a valved communication with said heater, and in which the expansive action of the flexible-diaphragm piston-motor controls a valve within said motor for releasing it of pressure. The collapsing action of said diaphragm piston-motor suddenly controls the operation of the pump to blow out the heated air from the heater and 'replace it with cold air, which, being then confined within the chamber of the iieXiblediaphragm piston-motor and the heater, is immediately expanded to drive out the ilexible piston-motor, and by direct connection of its pistonrod impel the power-transmitting shaft.

The piston is formed 'of metal disks anda flexible or elastic diaphragm, of any suitable air-tight material, and which is protected and supported from undue yielding and strain by one or more independent layers or covers of canvas or other similar material.

The connection of the pump and motor must be such as to render the pumping action sudden and to iill the heater with cold air while thevalve of the piston-'motor chamber is open and about to close, and thus the pump does not operate against pressure and little power is consumed in its air-forcing movement.

.Referring to the accompanying drawings, Figure l represents a vertical section of a calorie engine embracing my invention, the ilexible-diaphragm piston-motor being shown as extended and the relief-valve open 5 Fig. 9, a similar section, the ileXible-diaphragm piston- (Model.)

motor being shown as collapsed, its valved chamber closed, and the air-p u m p havin gforced cold air into the heater; Fig. 8, a vertical section taken at right angles to Fig. l; Fig. 4, a horizontal section oi' the air-heater, and Fig.

5 a section of the iiexible-diaphragm pistonmotor.

In the several ligures the same letters des- 6o ignate the same parts.

It is a primary feature of my invention that both the motor and the air-pump are formed of flexible-diaphragm pistons, each having a piston-rod, and each having connection through such piston-rods.

A suitable trame supports the operating parts, the arrangement of which is preferably such as shown, and in which the motor is suitably supported near the top, the ainpump near 7o the bottom, and the air-heater in intermediate position upon such frame.

The motor proper consists of a Valved chambei', a, formed within and by a suitable armed casting, b, and a flexible diaphragm, c, forming 7 5 the upper side of said chamber and secured by a clamping-ring, d, and provided with metal disks c, forming a broad piston-head, from which a piston-rod, e', extends upward centrally. The diaphragm is of vulcanized rnb- 8o ber, to bear a heat of, say, 3000 Fahrenheit, and is air-tight. It is re-enforced by a layer or layers of canvas or other similar covering, c2, to protect and support it from undue strain and yielding to pressure. Such supplemental covering may be on both sides of the elastic diaphragm 5 but I prefer and deem it only necessary to use it on the outer side; but the independent layers of canvas and rubber of the flexible piston are an important matter in ren- 9o dering it durable and equal for the strain, and upon this or equivalent construction of the diaphragm depends the successful operation of the engine. This iiexible piston-motor connects directly with the power transmitting crank-shaft j' by a connecting-rod, j", While a cross-head, f2, and guide-rods f3, moving therewith, give proper support to the piston-rod.

The air-pump shown forms a similar flexible piston with a valved chamber, a', butin which 10o the flexible diaphragm c forms the lower side of said chamber, is secured by a ring, d', and provided with metal disks c2, from which the piston-rod c3 extends downward centrally and axially coincident with the piston-rod of the motorproper. The air-pump,however, may be of any suitable form and construction so long as it has a yielding side. The piston-rod c3 connects by a cross-head, f4, moving in frameguides f5, to give the proper support to the piston-rod, and as means by which to connect it with the power-transmitting shaft. The rods z' z', by which this connection is made, are attached to each end of the cross-head f4 and to cranks jj on each end of the power-transmitting crank-shaft. This crank-connection, however, is by slots j i/,in connection with which the cranks jj must bear certain relation to the motor-crank of the driven shaft, for a purpose to be presently stated.

The heater is located intermediately with the motor and with the pump7 and consists of a cast-metal closed box, lc, provided with separated ribs 7e', rising from its bottom to near its top, and leaving a space, k2, at its opposite ends, as shown in Figs. 3 and 4. The ribs are near together, are readily heated from the bottom plate, with which they are cast, and form a large heating-surface to insure the immediate expansion of the air as soon as it is confined.

The chamber a of the flexible pistou-motor has a continuous communication with the space k2 at one end of the heater by the pipe l, and the chamber a' ofthe air-pump connects with the space 702 at the opposite end of the heater by the pipe l', which, however, is provided with a valve, l2, arranged to open outward from the pump-chamber, as shown in Fig. 3.

The spaces between the ribs 7c' open into the space 7a2, and for the purpose of preventing the air-currents from blowing through a few of the central spaces of the ribs I provide the plate m, depending from the top of the heater in close proximity to the ends of the ribs and between them and the end of the airconducting valved pipe l', which extends within the space 7a2 and just above the lower edge of the plate m, which thus serves as an apron to equalize the passage of the cold air into and through the spaces of the heater. The small space between the top of the heater and the top of the ribs is to prevent the heat being conducted to thetop plate, and thus wasted. This isolation of the top of the heater' gives an important advantage in utilizing the heat from the multiple walls of the heater.

The unyielding side of the flexible pistonmotor chamber is provided with a valve, a, opening inward, and it is automatically opened by means of an arm, o, pi'voted to the frame and operated by a tappet or catch, 0', on one of the guide -rods f3 of said flexible pistonmotor, when the latter' has nearly reached its limit of distention.

rlhe air-pump is provided with a valve, p, also opening inward, and carried by the yielding side of the rnnnp-chamber, and,like the valve Z2, is opened and closed by the movement of the pump-diaphragm.

It is important to the successful working of the motor that the pump shall have a quick pumping action, and at a particular part ot' the stroke of the iiexible piston-motor, and for this purpose the cranks j j of the power-transmitting shaft must be of such length and have such relation to the piston-motor connecting crank jz, and to the upper ends of the slots jj of the connecting-rods M, as to cause said cranksj to lift. the exible diaphragm otl the pump-chamber when the cranks j j nearly reach their highest point, thereby pumping fresh cold air into the heater and forcing the hot air out as the flexible piston-motor is closing within its chamber. It is important in this connection that the pump-chamber and the heater shall be about three times the area of the chamber of the flexible-diaphragm piston-motor, so as to insure a supply of cold air that will give the requisite expansive force upon the broad piston. As the motor-diaphragm descends the valve in the chamber of said motor,'having been held open by friction, closes by reason of being pressed upon by the descending piston. The rods which connect with the pump-diaphragm also descend, and carrying with them said diaphragm allow the valve L2 in the heater connecting-pipe Z to close, while the valvep in said diaphragm opens, thereby iilling the large pump-chamber with cold air, to be pumped into the heater at the proper time to operate the piston by its expansive force, and during such expansion it is confined within the heater and the motorchambers by the closing of the valve Z2, placed in the pipe which supplies the heater with the air from the pump. In this way the powertransmitting shaft is revolved by the action of the motor diaphragm piston.

The heat is applied to the bottom of the heater, and in an engine for operatin g a sewingmachine it may be furnished by a suitable oil or gas stove placed on the top of the pump and within a suitable box depending from the heater. For a larger engine a coal-re may be suitably arranged. By this construction a sufficient power can be obtained to operate a sewing-machine or a churn at an expansive temperature of the air of from 250O to 3000, and which will not injure the rubber diaphragm.

Avulcanized diaphragm is not essential for the pump, but it may be of oil-cloth or other suitable air-tight material re-enforced by separate layers of canvas. The chamber of the piston-motor lnay be either cast or formed of pressed sheet metal.

rI he movement of the piston motor diaphragm is equal to about one-third its diameter, and it is free from the friction incident to a cylinder and piston-head, and is easily renewed when necessary.

As a small engine it will be found efficient and durable and comparatively of little cost. An important advantage in its construction is the pumping ofthe air into the heater comparatively free from pressure, and therefore there is little power expended to work the IOO IIO

pump during the descending movement of the piston-motor; and by making the cranks jj and the slots withi n which they work of suitable length, the raising of the pump-diaphragm may be effected in a quarter-revolution of the driven shaft, and this action is timed by the proper placing of these cranks relative to the piston-rod crank of the motor. The power is transmitted from a pulley, A, on the driven shaft, which is of sufficient weight to act also as a fly-wheel.

It is important to notice that the valve a is so hinged as to be held open by the friction or tightness of its hinge, and that the whole dischc rge of the heated air, of which the cold air takes its place, is through this valve, as follows, viz: The crank-shaft revolving to the right, the short crank j2 havin g passed the center, and the valve having been open since said crank was about the same distance on the other side of the center, thus gives time for the pressure in the chamber to pass olf. The valve still remains open, while the slotted cranks now operate the pump, blowing out the hot air through this open valve till these cranks reach the vertical point, by which time the main crank has descended, so that the piston is pressing upon and closingthe valve. v

I am aware that prior to my invention single and double diaphragms of rubber have been used in motors and gas-regulators; that such diaphragm hasbeen made with a layer or facing of tin-foil or other iiexible metallic coating to protect the rubber and render it'impervious to gas, and that a molded diaphragm composed of two or more strata of vulcanized rubber has been used with interposed stratum of textile fabric but my improved piston-dia phragm differs from these things in being composed of a rubber diaphragm to form an airtight chamber, and one or more independent diaphragms of canvas upon the outer surface of the rubber diaphragm, the function of which is to receive and bear all the strain upon the rubber diaphragm and prevent it from being unduly distended, the action of which would in a short time disintegrate the rubber. In fact, the canvas is the supporting and operating connection for the power-transmittin g rod,

the rubber being used only for its air-tight qualities. Its use as a propelling material under constant movement and strain renders it inadequate for the purpose of a piston motor. It cannot withstand propelling force. Moreover, it has been found in practice that the action of the canvas support for the propelling-rod must be to a certain extent independent of the air-tight diaphragm, in order to restrain the action of the latter within its normal limits and to give a free support to the rubber diaphragm, and in this function it is of prime importance to the successful use of a rubber diaphragm as a propelling-piston.

In a caloric engine, I claim- 1. The combination of a flexible-diaphragm piston-motor, a separate flexible-diaphragm air-pump, and a closed air-heater having continuous communication with the chamber of said flexible-diaphragm piston-motor and a valved communication with the chamber of said air-pump, the flexible diaphragm of said air-puinp bein g connected with and controlled by the iiexible diaphragm of said piston-motor for controlling the admission of air to said heater.

2. The combination of a flexible-diaphragm piston-motor, a fiexible-diaphragm air-pump, and a closed air-heater, with a valve in the chamber of said piston-motor, and a pivoted arm operated by the diaphragm of said pistoninotor to open said valve, by pressure for relieving said piston-mol or ofthe expansive force of the air in the heater.

3. The combination ot' a iieXible-diaphragm piston-motor, a flexible-diaphragm air-pump, and a closed air-heater, constructed for conjoint operation, substantially as herein set forth, the said airpump having a free operative crank-connection with the driven crankshaft of the said piston-motor for effecting a quick movement of the pump, for the purpose stated.

4. The closed air-heater, consisting of the case or box having an uninterrupted closed bottom and solid separated ribs rising therefrom, but not touching the top nor the ends of said heater, for increasing the air-heating surface within said closed case or box, in combination with the cold-air-pump-supplying pipe, and the flexible-diaphragm piston-motor, substantially as herein set forth.

5. rlhe closed air-heater provided with interior separated ribs rising from the bottom, but not touching the top nor extending to the opposite ends of said heater, leaving uninterrupted end spaces, in one of which an apron, m, depends in position to equalize the circulation and passage of the cold air from the pump-supplying pipe into and through said heater.

6. The closed air-heater communicating by a'pipe from one end and from the top thereof with the chamber of the piston-motor, and communicating with the chamber of the airpump by a pipe extending into and from the bottom of the opposite end of said heater for causing the air to be impelled into and through said heater from one end to the other in its course to said piston-motor chamber.

7. The combination of a iiexible-diaphragm piston-motor provided with avalve controlled by and for controlling the operation of said motor, a iiexible diaphragm air-pump controlled by said piston-motor, and a closed airheater, with a valve arranged in a pipe which connects said pump and heater, and opened and closed by the action of the pump, for the purpose stated.

S. The flexible-diaphragm piston-1notor and the flexible-diaphragm pistonpump, each connected by a centrallycoincidentpiston-rod, and with the power-transmitting crank-shaft, and having a connected heater arranged between them, the said piston-rods extending in oppo- IIO site directions an d suitably supported by guides in the frame of the engine.

9. The combination of :i iiexible-dieplirngm piston-motor h win g :i valve controlled substantially as herein set forth, :L flexible-dinl ihrzig'm piston-puinl'), and ziclosed nir-heater eonimunicating with said piston-motor und air-pump, with the slotted rods t', connecting,` sziid pump with the pourrir-tunisinitting shaft und the said piston-motor, to effect the objects stated.

10. The iiexiblediaphragm piston motor, provided with it valve opening within its ohznnber by outward pressure, in coinbilnition with the pivoted erin o and the aetuzttingp'mppei'y o', carried und controlled by the cross-head guides oi' said piston-inotori'or controlling the operation of said valve to control the operation of sid piston-motor.

11. The flexible diaphragm of zi piston-niotor,consistin g of an uir-tightru bber diaphragm, c, und an outerindepemlent support of canvas, c, in combination with the power-transmitting rod c', the middle clamping-plates, e, and the casing b, substantially :is und for the purpose specified.

1n testimony whereof I have hereunto setlny hand in the presence of two subscribing` witnesses.

JABEZ JENKINS.

\Vitnesses:

JOHN F. DURVEN, THOMAS D. J Mms. 

